Michael

I just checked my cable modem lights and they indicate that both upstream and downstream are bonded. So upstream has a minimum stream speed of at least 54 mbps and downstream has a minimum stream speed of 76 mbps. Unfortunately the front lights don't tell me if more than 2 channels are bonded in either direction and no one on the internet seems to know how many channels are currently being bonded by Comcast for DOCSIS 3.0.

Michael

I don't understand why FIOS won't have similar saturation issues as cable. I understand that cable may put 200 homes on the same frequency (could be 8 QAM256 channels for downloading using 48 MHz of the cable bandwidth) possibly causing saturation and FIOS handles the traffic independently but when FIOS backhauls 200 homes, then I would think they would have to combine those all those separate packets into one stream possibly creating saturation. It seems that one is combining packets on the front end and the other is combining packets on the backend or am I missing how FIOS works.

From my understanding, fiber in the streets can get to about 1.2 GHz of bandwidth using about 6 amplifiers per mile. Whether it is cable or FIOS, neither can exceed that bandwidth for all services provided. For either cable using DOCIS 3.0 or FIOS, it would seem that both are restricted by the bandwidth on the fiber available for internet traffic.

I'll admit that with DOCSIS 2.0, the bandwidth could not be expanded beyond one channel (6 MHz) which was a very limiting factor and suspect that is probably the reason that most cables limited download speed to about 15 mbps several years ago but DOCSIS 3.0 with the correct hardware can expand the bandwidth and bitrate of the stream to any size that can be provided by the cable company. Although most current DOCSIS 3.0 modems are limited to 4 or 8 channels maximum so therefore are limited but there in no limitation on the number of channels that can be supported by a DOCSIS 3.0 modem and therefore the main limitation in the future should be the amount of bandwidth available for internet traffic as more channels are supported by the newer modems.

It seem hard to believe that FIOS could maintain 50 mbps download simultaneously for 200 homes since that would require over 1 GHz fiber bandwidth just for internet traffic even if FIOS can get a 50% increase in bitrate for the same bandwidth as QAM256. The only way I could see that as being possible without significant degradation would be is if FIOS has a significantly higher throughput fiber or has two sets of fiber, one for the internet and another for TV. I realize that in the real world that would never likely happen but I don't see a significant difference of having cable supporting the same bitrate on the front end as FIOS would on the backhaul for the same number of homes.

hungryhorace

Some questions.

1. Do you know what a UBR is?
i. Are you aware of the difficulties experienced with providing locally contented UBRs?

2. Do you know the difference between a symmetric product and an asymmetric one?

3. Are you aware that FIOS offers a symmetrical product?

4. Are you aware of the reason why coaxial cable products can only offer limited upstreams compared to FTTP products?

You (still) don't seem to be able to understand that Comcast is a locally contended product and FIOS a nationally contended one.

hungryhorace

Above is the biggest point you're missing. This is the third time i'm saying this now; Comcast (and other cable providers) operate a UBR (universal broadband router) that is connected to local cable 'cab' boxes. If usage in a street, or an apartment block, or similar is high then the local UBR becomes saturated. Cable providers are unable to contend their traffic in a more efficient manner (ie, nationally) hence introducing traffic management to try and ensure their network doesn't get clogged.

FIOS suffers from none of these issues.

1. They're fibre ALL THE WAY to the premises, not just to the local cab box then coax the rest.
2. The product is nationally contended, bypassing any local bottlenecks that build up ala cable providers.

jeffreyhy

With 4 devices going simultaneously, the 'roadblock' isn't your own home wireless network, is it?

Regards, JEff

thinbrit

It is unusual for that to be the case with mainstream sites or services. Almost without exception, they all use CDNs to deliver their content. Bottlenecks are typically with your internet service provider.

Colleagues have DSL connections that claim to be 35 Mbps, but they are contended (so 50 people might all have 'up to 35Mbps connections' but they all route out of a connection that does not support all 50 users connected at full speeds at the same time). Their speeds drop dramatically during peak hours.

I have a 10 Mbps connection at my ranch via a directional 5GHz long range wireless access point that hits a another repeater on a water tower some 18 miles away (I live in the boonies). The service is dedicated and uncontended. I have no problems running multiple streams of HD video, VPN connection to the office, etc. My connection is 10Mbps via my provider, at all times. During peak times, my 10Mbps connection is better than my colleagues ('up to') 35Mbps connection.

At my office (in the metroplex) I have a dedicated 1Gbps fiber connection. That rocks.

In a nutshell, if you are using a contended connection then the ISP and location are big factors. A quoted faster connection may or may not be faster than a quoted slower connection speed at peak hours.

The speed limit on the M4 is 70 mph. If few others are using it you can do 70 mph, at rush hour chances are you will be doing 50 mph. An uncontended connection is like being given the M4 bus lane to travel down.

Markoncarp

Wow. Geekfest.

md95065

Well, the one thing that I do understand is that FIOS is not available where I live and probably won't be for some considerable time so all of this discussion is moot as far as I am convcerned ...